Kensington Palace announced the news on October 15 2018, as the couple arrived in Australia for their royal tour. They tweeted a statement saying the couple were “very pleased to announce that The Duchess of Sussex is expecting a baby in the spring of 2019.”

“Their Royal Highnesses have appreciated all of the support they have received from people around the world since their wedding in May and are delighted to be able to share this happy news with the public.”

Their Royal Highnesses The Duke and Duchess of Sussex are very pleased to announce that The Duchess of Sussex is expecting a baby in the Spring of 2019. pic.twitter.com/Ut9C0RagLk

However, the couple may decide to surprise everyone when naming their first child.

Canadian-born Autumn Phillips, and husband Peter Phillips, opted for a non-traditional name for their daughter Savannah – the Queen’s first great-grandchild – in 2010.

In the US, the most popular name for a baby girl is Emma and Liam for a baby boy.

In the UK, the most popular name for a girl born in 2017 was Olivia, and for a boy Oliver.

Where will the baby fall in the line of succession?

Seventh in line. The baby will bump Harry’s uncle the Duke of York into eighth place in the line of succession.

Princesses Beatrice and Eugenie move into ninth and 10th place, and the Earl of Wessex – the Queen’s youngest son – drops out of the top 10 for the first time to 11th in line.

Meghan and Harry married on May 19, 2018 (Photo: Getty)

How will the baby be related to the Queen?

The baby will be a great-grandchild of the Queen and the Duke of Edinburgh, and the Prince of Wales’s grandchild and the Duke and Duchess of Cambridge’s niece or nephew.

Will he or she ever be monarch?

Unlikely. The baby will have three cousins Prince George – a future king – and Princess Charlotte and Prince Louis, who are further up the line of succession, so it is a safe bet that throne will stay on the Cambridge side of the family.